Run Claude Code on docker

claude.sh

#!/bin/bash

set -xe

IMAGE_NAME="claude-code-docker"
DOCKERFILE_PATH="$(dirname "$0")/Dockerfile.claude"

# Build the image if it doesn't exist
if ! docker image inspect "$IMAGE_NAME" &> /dev/null; then
    echo "Image $IMAGE_NAME not found. Building..."
    docker build -f "$DOCKERFILE_PATH" -t "$IMAGE_NAME" "$(dirname "$0")"
fi

# Ensure Claude config directory and file exist
mkdir -p "$HOME/.claude"
touch "$HOME/.claude.json"

# Run Claude Code in Docker container
# - Mount current directory to /workspace
# - Mount Claude config directory and file for authentication persistence
# - Pass current user UID/GID to maintain file permissions
# - Interactive with TTY for proper CLI experience
docker run -it --rm \
    -e HOST_UID="$(id -u)" \
    -e HOST_GID="$(id -g)" \
    -e HOST_USER="$USER" \
    -e HOST_HOME="/home/$USER" \
    -v "$PWD:/workspace" \
    -v "$HOME/.claude:/home/$USER/.claude" \
    -v "$HOME/.claude.json:/home/$USER/.claude.json" \
    -w /workspace \
    "$IMAGE_NAME" "$@"

Dockerfile

FROM debian:latest
                                                                                                                                                                                             
# Install dependencies                                                                                                                                                                       
RUN apt-get update && apt-get install -y \                                                                                                                                                   
    curl \                                                                                                                                                                                   
    git \                                                                                                                                                                                    
    ca-certificates \                                                                                                                                                                        
    gnupg \                                                                                                                                                                                  
    sudo \
    && rm -rf /var/lib/apt/lists/*

# Install Node.js (required for Claude Code)
RUN curl -fsSL https://deb.nodesource.com/setup_20.x | bash - \
    && apt-get install -y nodejs \
    && rm -rf /var/lib/apt/lists/*

# Install Claude Code globally
RUN npm install -g @anthropic-ai/claude-code

# Create workspace directory
RUN mkdir -p /workspace

# Set working directory
WORKDIR /workspace

# Script to create user matching host UID/GID and run Claude
COPY entrypoint.sh /entrypoint.sh
RUN chmod +x /entrypoint.sh

ENTRYPOINT ["/entrypoint.sh"]

entrypoint.sh

#!/bin/bash

# Create a user with the same UID/GID as the host user
# This ensures files created in the container have the correct ownership

USER_NAME="${HOST_USER:-claude-user}"
USER_UID="${HOST_UID:-1000}"
USER_GID="${HOST_GID:-1000}"
USER_HOME="${HOST_HOME:-/home/$USER_NAME}"

# Create group if it doesn't exist
if ! getent group "$USER_GID" > /dev/null 2>&1; then
    groupadd -g "$USER_GID" "$USER_NAME"
fi

# Create home directory first to avoid useradd warnings
mkdir -p "$USER_HOME"

# Create user if it doesn't exist
if ! id "$USER_UID" > /dev/null 2>&1; then
    useradd -u "$USER_UID" -g "$USER_GID" -d "$USER_HOME" -M -s /bin/bash "$USER_NAME"
fi

# Ensure .claude directory and file exist
mkdir -p "$USER_HOME/.claude"
touch "$USER_HOME/.claude.json"

# Set ownership on home directory and all contents
# Do this explicitly for the directory itself and its contents
chown "$USER_UID:$USER_GID" "$USER_HOME"
chown -R "$USER_UID:$USER_GID" "$USER_HOME/.claude"
chown "$USER_UID:$USER_GID" "$USER_HOME/.claude.json"

# Ensure the user has access to workspace
chown -R "$USER_UID:$USER_GID" /workspace 2>/dev/null || true

# Make sure home directory and config files are writable
chmod 755 "$USER_HOME"
chmod -R u+w "$USER_HOME/.claude"
chmod u+w "$USER_HOME/.claude.json"

# Switch to the user and run Claude Code
exec sudo -u "#$USER_UID" -g "#$USER_GID" HOME="$USER_HOME" claude "$@"